https://apnews.com/0ad68859a96a4129a5e11294c73466be

LOS ANGELES (AP) — To show that Katy Perry and the team that wrote her 2013 hit "Dark Horse" may have heard his song and stole from it, Christian rapper Marcus Gray's primary evidence was that his 2009 song, "Joyful Noise" had plays in the millions on YouTube and Spotify.

Plaintiffs in copyright cases like Gray, who won a $2.78 million victory over Perry and her co-writers on Thursday, must prove that the artist who stole from them had a reasonable opportunity to hear a song that was widely disseminated, a principle lawyers simply refer to as "access."